Authors:
Rizwan Ahmad Khan; Rahul Sharma;
Abstract:
This study was conducted to investigate the strength and water permeation properties of Rice Husk Ash (RHA) concrete reinforced with polypropylene fibres (PP). The properties evaluated include compressive strength, splitting tensile strength, flexural strength, initial surface absorption test (ISAT) and capillary suction test
(sorptivity). An experimental program was planned, in which thirteen concrete mixes were prepared. Ordinary Portland Cement (OPC) was partially replaced by RHA at 10%, 15% and 20% with addition of PP at 0.5%, 0.75% and 1% by weight of binder. The water/binder (w/b) ratio was kept constant at 0.38. Super-plasticizer was varied from 0.3% to 0.7% by weight of binder for different concrete mixes. The use of RHA in concrete mixes was found to increase the compressive strength at later ages and inclusion of higher amount of PP decreases compressive strength. The splitting tensile strength was found to increase with RHA as well as PP for all concrete mixes. There was significant enhancement in flexural strength with increase in PP content,
especially at later ages. Initial surface absorption test and capillary suction test showed that as the replacement of cement by RHA in concrete mixes increases, water absorption in concrete mixes was found to decrease compared to control mix. Addition of PP also decreases ISAT-10 and initial rate of absorption (IRA) values,
but RHA has more effect on the reduction of absorption characteristics than PP.
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